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Animal Plasma

Animal plasma is present in all foods that contain meat, as they also contain blood as part of the meat. The animal plasma included in Wysong diets is porcine in origin. The nutritional advantages of plasma as an added ingredient beyond that which is naturally in meat is partly due to immunologic fractions, including IgG, similar to what is found in the colostrum in breast milk. Plasma also contains haptoglobulin, growth factors, other proteins and peptides, and transferrins. The protein fraction of plasma is highly digestible and plasma also increases digestibility of other ingredients, including fiber.

Some of the research showing the benefits of plasma:

  • Spray-dried animal plasma (SDAP), as present in certain Wysong animal foods, is widely used in diets of domestic animals to improve feed intake, growth, feed efficiency, and intestinal health.

  • SDAP contains significant amounts of functional proteins, including IgG (similar to that found in the colostrum in breast milk), transferrin, haptoglobulin, and several hormones and growth factors. These proteins exert effects within the intestine independent of their nutritional value. Although the exact nature of the fiber digestibility improvement is unclear it may be mediated through changes in intestinal function.

  • A summary of 48 controlled studies concluded that effects of SDAP on growth and intake in pigs are mediated by improving immunocompetence of the animal.

  • Different studies have compared SDAP with antimicrobials in diets of pigs and calves and concluded that immunological components (e.g., IgG) contribute to improved enteric health and resistance to both natural and experimental pathogen challenge.

  • One study reported that feeding SDAP to young pigs resulted in reduced mRNA expression of tumor necrosis factor-α and interleukin-1ß mRNA in the adrenal gland, spleen, hypothalamus, pituitary gland, and liver. The authors also reported changes in the ratio of villus height to crypt depth in pigs fed diets containing SDAP.

  • Jiang et al. (2000) reported that feeding SDAP to early-weaned pigs reduced cellularity of the lamina propria of the small intestine and improved efficiency of dietary protein utilization, in part, by decreasing intestinal amino acid catabolism.

Most recent study (2004) to prove the positive relationship between plasma and fiber digestibility:

  • Aim: Effects of spray-dried animal plasma (SDAP) on intake and apparent digestibility of major dietary components were determined using 22 adult Beagles.

  • Results: Addition of SDAP did not markedly affect chemical composition of diets and did not affect intake. Digestibility of DM was improved (P < 0.04) an average of 3.2% when 2% SDAP was included in the diet for all trials. Organic matter digestibility was improved (P < 0.01) in Trials 2 and 3 by an average of 2.9%. Also, digestibility of crude fiber (Trials 1 and 2) or total dietary fiber (Trial 3) was increased with addition of SDAP to the diet (P < 0.01).

  • Conclusion: Spray-dried animal plasma was an acceptable ingredient in dry dog food preparations, resulting in improved digestion and decreased fecal output


Bergström, J. R., J. L. Nelssen, M. D. Tokach, R. D. Goodband, S. S. Dritz, K. Q. Owen, and W. B. Nessmith, Jr. 1997. Evaluation of spray-dried animal plasma and select menhaden fish meal in transition diets of pigs weaned at 12 to 14 days of age and reared in different production systems. J. Anim. Sci. 75:3004–3009.

Coffey, R. D., and G. L. Cromwell. 1995. The impact of environment and antimicrobial agents on the growth response of early-weaned pigs to spray-dried porcine plasma. J. Anim. Sci. 73:2532–2539.

Coffey, R. D., and G. L. Cromwell. 2001. Use of spray-dried animal plasma in diets for weanling pigs. Pig News and Info. 22:39N–48N.

Hunt, E., Q. Fu, M. U. Armstrong, D. K. Rennix, D. W. Webster, J. A. Galanko, W. Chen, E. M. Weaver, R. A. Argenzio, and J. M. Rhoads. 2002. Oral bovine serum concentrate improves cryptosporidial enteritis in calves. Pediatr. Res. 51:370–376.

Jiang, R., X. Chang, B. Stoll, M. Z. Fan, J. Arthington, E. Weaver, J. Campbell and D. G. Burrin. 2000. Dietary plasma protein reduces small intestinal growth and lamina propria cell density in early weaned pigs. J. Nutr. 130:21–26.

Jiang, R., X. Chang, B. Stoll, K. J. Ellis, R. J. Shypailo, E. Weaver, J. Campbell, and D. G. Burrin. 2000. Dietary plasma protein is used more efficiently than extruded soy protein for lean tissue growth in early-weaned pigs. J. Nutr. 130:2016–2019

Kats, L. J., J. L. Nelssen, M. D. Tokach, R. D. Goodband, J. A. Hansen and J. L. Laurin. 1994. The effect of spray-dried porcine plasma on growth performance in the early-weaned pig. J. Anim. Sci. 72:2075–2081.

Quigley, J. D., III, and M. D. Drew. 2000. Effects of oral antibiotics or IgG on survival, health and growth in dairy calves challenged with Escherichia coli. Food Agric. Immunol. 12:311–318.

Quigley, J. D., C. J. Kost and T. M. Anspach. 2002. Effects of oral immunoglobulins and oligosaccharides in calf milk replacer formulations. J. Dairy Sci. 85:413–421.

Quigley, J.D., J. M. Campbell, J. Polo and L. E. Russell. 2004. Effects of spray-dried animal plasma on intake and apparent digestibility in dogs. J. Anim. Sci. 2004. 82:1685-1692.

Torrallardona, D., M. R. Conde, E. Esteve-García, and J. Brufau. 2002. Use of spray dried animal plasma as an alternative to antimicrobial medication in weanling pigs. Anim. Feed Sci. Technol. 99: 119–129.


Q: Are there any communicable disease concerns created by adding Plasma?

A: No more than would be transmitted by eating any meat (which contains whole blood). After heat processing it is very safe. Remember, animals in the wild eat whole raw meat and blood with great benefit and optimal health.

Q: Is Plasma added to other Wysong foods?

A: Yes, it is in our Au Jus™ canned products as well as our Stew Diets™.

Q: I have been a long time customer and I have noticed that the Au Jus™ canned diets now have animal plasma listed as an ingredient. I have read your statement on the Wysong website regarding the animal plasma. I still do not understand why animal plasma has been added. I know that animal plasma is a "cheap" ingredient and is bad for pets. Only pet food companies who produce poor quality food use animal plasma as an ingredient. I do not agree that animal plasma has nutritional benefit; it is just a junk by-product. I find it very suspect that your company has chosen to use such a cheap, poor quality ingredient. Additionally, the Whole Dog Journal has dropped Wysong from the top ten-dog food list. I called them to find out why and they said it was because Wysong added animal plasma to their food. Why would you add such a horrible ingredient to your pet food?

A: We have supplied you with the facts on plasma and have given you scientific references. 

Although there are myths about plasma perpetuated by those who wish to feed based upon identifying boogeyman ingredients, demonizing plasma makes no more sense than demonizing meat as a food for carnivores.

As for a 'rating' from the magazine you spoke of, we do not construct foods or advise people based upon the faulty criteria they use.  Health is our number one objective. 

They obviously have agendas other than the health of pets or are misinformed.  We have sent them the appropriate criteria for evaluating foods if health is the objective.  They have ignored it and chosen to use myth, lore and fable, rather than facts and science. 

We are staffed and led by doctorate level researchers with 35 years of experience in the field.  That cannot be said for any other manufacturer or for self-proclaimed experts on staff at magazines. 

Our objective is the health of your pet.  If that is your objective too, we encourage you to use the Internet and to learn from our website and printed materials.